Griffin Air Special Parameters
Written by Daan de Waard
Updated at March 14th, 2026
Table of Contents
Purpose
This document provides a brief overview of how to configure the ‘special’ parameters on the Griffin-Air. For configuring the ‘standard’ parameters, please reference the setup guides for the Oyster3-Global.
Special Parameters
The System Parameter tabs that are specific to the Griffin-Air are the following:
- Barometer
- Ground Mode (Adv)
- Location Preferences (Adv)
- Geolocation (Adv)
Barometer
There are 3 main barometer modes. The selected mode is used in conjunction with a configurable pressure threshold to configure conditions for a pressure trigger. The modes are as follows:
Absolute: The trigger evaluates the current pressure against a known pressure level. This is used in cases where you know exactly what the atmospheric pressure needs to be to set off the trigger. You can set this High or Low, depending on whether you are interested in detecting periods of increased pressure or decreased pressure.
Delta: The trigger is set for changes in pressure that exceed a certain level. Setting this to ‘High’ allows you to detect pressure changes that increases more than a specific level over the configured period. Setting this to ‘Low’ allows you to detect pressure changes that decrease more than a specific level over the configured period. The trigger is cleared once the infraction stops, regardless of the final pressure attained.
Relative: The trigger is set similarly to the delta trigger, but the trigger is not cleared after the infraction has ended. After either increasing or decreasing beyond the configured threshold, the pressure needs to change by the same amount in the opposite direction in order to clear the trigger.
See the images below for the illustrated operation:
Barometer Parameter clarifications:
Active Level: The default value of ‘Outside Threshold’ means that the trigger will be true for conditions described by the green areas in the illustrations above. By setting this to ‘Within Threshold’, the red and green areas above would be swapped.
Pressure Threshold: This is measured in hectopascals and should be set depending on the mode. If the mode is Absolute, the value must be an atmospheric pressure (e.g. 1000hPa at sea level). For the other modes, this value must be a differential pressured (e.g. 20hPa to detect a change of 20hPa in the atmospheric pressure, whatever it might be).
Hysteresis: The hysteresis is always specified as a differential pressure (e.g. 10hPa). It does not need to be set to a non-zero value. The purpose of it is to reduce frequent triggering for pressures that linger around the threshold value. The hysteresis value affects the value of the threshold upon de-trigger. How it does so is described in the illustrations above.
Debounce Time: As with the hysteresis, the debounce time is used to prevent frequent triggering for pressure changes that linger around the threshold value. Once triggered, the device will suppress reporting the trigger for this period of time. After the period has elapsed, it will check if the trigger is still valid before reporting it. The value should be short if you are expecting rapid transients that should be valid triggers, otherwise it can be set to a longer value if you are expecting nuisance fluctuations around the trigger threshold.
Recalibration Period: This does not apply to the Absolute mode. This value sets a timer for re-zeroing the differential pressure reference. This is very important to set correctly. As per the illustrations above, the differential thresholds are evaluated according to this time period. Hence, a valid pressure change needs to occur within this period of time to set or unset the trigger. This should be set based on testing for the specific application. It is not recommended to disable this for the differential modes, as the reference pressure is never recalibrated, so the differential pressure will be evaluated according to the pressure measured at device bootup.
Log on Calibration Period: This does not apply to the Absolute mode. This is useful for initial pressure profiling and testing, as it allows you to capture the current pressure value at regular intervals.
Ground Mode
Some important remarks:
Ground Mode detection is disabled by default. It needs to be explicitly enabled.
Detection relies on the barometer module. This needs to be enabled and configured for an appropriate trigger using the System Parameter tab in the previous section.
Detection relies on the accelerometer and jostle filter. These are enabled by default; however, it is worth configuring these according to preference using the ‘Accelerometer (Adv)’ and ‘Jostle Filter (Adv)’ System Parameter tabs.
Overview of operation:
When the device is NOT deemed to be in flight, it is said to be in ‘Ground Mode’. This is equivalent to ‘normal’ operation. When the device is detected to be in flight, it is said to have EXITED ‘Ground Mode’. In this state, the device goes into a sleep mode until it detects that it is no longer in flight. It may still log data and scan for Bluetooth tags in this state, but it will not perform uploads.
The triggers for exiting Ground Mode are accelerometer jostling and the barometer (whichever configuration the user has set in the System Parameters for it to trigger). Once one of these triggers becomes active, the device will either exit Ground Mode straight away, or it will first attempt to get a GPS fix if the GPS Fix Period is non-zero. The GPS fix is used as a temporary suppressor, whereby the device will not exit Ground Mode if it is able to get a fix and determines that the speed is below the configured threshold (meaning that the device is actually not in-flight). The GPS Fix Period determines how often the device checks for fixes if it is deemed to be in-flight as a failsafe to lingering triggers.
Ground Mode parameter clarifications:
Sensor Logic: By default, this is ‘EITHER’. This means that either accelerometer jostling, or a barometer trigger can cause the device to deem itself to be in flight and to exit Ground Mode. Setting this to ‘BOTH’ is a stricter condition, whereby both triggers are required for the device to exit Ground Mode.
Accelerometer Trigger End Duration: If the device registers a jostle, it will set the accelerometer trigger to be true for this duration. This means that if a device registers movement and then does not experience any movement thereafter, the trigger will still be held for this duration. If, at the end of this period, there is still movement, the trigger will be prolonged.
Barometer Trigger End Duration: Similar to the Accelerometer Trigger End Duration, but for the barometer.
GPS Fix Period: As described in the overview, this is how often the device attempts a GPS fix while the device is in a flight. This behaviour can be disabled for additional power saving, but it is not recommended from a failsafe perspective.
Speed Threshold: This is the speed limit that the device must adhere to if it gets a successful GPS fix while the flight triggers are active in order to suppress the flight condition temporarily and allow uploads again.
Location Preferences
It is possible to switch between the geolocation methods used for trip tracking and heartbeats. This can be set to use either/both GPS or/and Wi-Fi. A fallback method can also be set so that if the primary mechanism does not succeed (in the form of either a successful GPS fix or useful Wi-Fi access points), the alternative method will be used temporarily.
Take note that the GPS fixes attempted by the Ground Mode service are not affected by this parameter.
Geolocation
These parameters are used in the event that Wi-Fi geolocation is enabled, either as a primary or fallback mechanism. They are described according to the standard Edge device offering.
